Transmission bandwidth demands in telecommunication networks (e.g., the Internet) appear to be ever increasing and solutions are being sought to support this bandwidth demand. One solution to this problem is to use fiber-optic networks, where wavelength-division-multiplexing (“WDM”) technology is used to support the ever-growing demand in optical networks for higher data rates.
Conventional optical switching networks typically use wavelength routing techniques, which require optical-to-electrical-to-optical (“O-E-O”) conversions of optical signals at each optical switching node. O-E-O conversions at each switching node in the optical network is not only a very slow operation (typically about ten milliseconds), but it is very costly, and potentially creates a traffic bottleneck for the optical switched network. In addition, the current optical switching technologies cannot efficiently support “bursty” traffic that is often experienced in packet based communication applications (e.g., the Internet).
Recently, optical burst switching (“OBS”) schemes have emerged as a promising solution to support high-speed bursty data traffic over WDM optical networks. The OBS scheme offers a practical opportunity between the current optical circuit-switching and the emerging all optical packet switching technologies. It has been shown that under certain conditions, the OBS scheme achieves high-bandwidth utilization and class-of-service (“CoS”) by elimination of electronic bottlenecks as a result of O-E-O conversions occurring at switching nodes, and by using a one-way end-to-end bandwidth reservation scheme with variable time slot duration provisioning scheduled by the ingress nodes.
However, current signaling protocols, such as Just-In-Time (“JIT”) signaling, Just-Enough-Time (“JET”) signaling, or other one-way reservation protocols, employed to reserve network and device resources and to setup and teardown burst paths over OBS networks are complex and resource intensive. As such, expensive hardware, including powerful network processors and vast amounts of memory for tracking reservation protocol states, are required in each switching node of an OBS network. Despite the complexity of these signaling protocols, low loss of optical packets cannot be guaranteed. Furthermore, JIT and JET signaling are intimately wrapped up with the task of scheduling data packets for transmission. As such, JIT and JET are inflexible solutions that prevent easy modification of the signaling protocol or scheduling algorithm used at a given time on an OBS network.